[MemorySSA] Set LoopSimplify to preserve MemorySSA in the NPM, if analysis exists.
Summary:
LoopSimplify is preserved in the legacy pass manager, but not in the new pass manager.
Update LoopSimplify to preserve MemorySSA conditionally when the analysis is available (same behavior as the legacy pass manager).
Reviewers: chandlerc
Subscribers: mehdi_amini, jlebar, Prazek, george.burgess.iv, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D65418
llvm-svn: 367594
diff --git a/llvm/lib/Transforms/Utils/LoopSimplify.cpp b/llvm/lib/Transforms/Utils/LoopSimplify.cpp
index 7e6da02..e202b45 100644
--- a/llvm/lib/Transforms/Utils/LoopSimplify.cpp
+++ b/llvm/lib/Transforms/Utils/LoopSimplify.cpp
@@ -835,12 +835,19 @@
DominatorTree *DT = &AM.getResult<DominatorTreeAnalysis>(F);
ScalarEvolution *SE = AM.getCachedResult<ScalarEvolutionAnalysis>(F);
AssumptionCache *AC = &AM.getResult<AssumptionAnalysis>(F);
+ auto *MSSAAnalysis = AM.getCachedResult<MemorySSAAnalysis>(F);
+ std::unique_ptr<MemorySSAUpdater> MSSAU;
+ if (MSSAAnalysis) {
+ auto *MSSA = &MSSAAnalysis->getMSSA();
+ MSSAU = make_unique<MemorySSAUpdater>(MSSA);
+ }
+
// Note that we don't preserve LCSSA in the new PM, if you need it run LCSSA
- // after simplifying the loops. MemorySSA is not preserved either.
+ // after simplifying the loops. MemorySSA is preserved if it exists.
for (LoopInfo::iterator I = LI->begin(), E = LI->end(); I != E; ++I)
Changed |=
- simplifyLoop(*I, DT, LI, SE, AC, nullptr, /*PreserveLCSSA*/ false);
+ simplifyLoop(*I, DT, LI, SE, AC, MSSAU.get(), /*PreserveLCSSA*/ false);
if (!Changed)
return PreservedAnalyses::all();
@@ -853,6 +860,8 @@
PA.preserve<SCEVAA>();
PA.preserve<ScalarEvolutionAnalysis>();
PA.preserve<DependenceAnalysis>();
+ if (MSSAAnalysis)
+ PA.preserve<MemorySSAAnalysis>();
// BPI maps conditional terminators to probabilities, LoopSimplify can insert
// blocks, but it does so only by splitting existing blocks and edges. This
// results in the interesting property that all new terminators inserted are